Technical Field
The present invention relates to a high strength special steel of which strength and fatigue life are improved by adjusting ingredients and contents to control types, sizes, and formation amounts of carbide and boride.
Description of the Related Art
Currently, a method of manufacturing a component in a hollow shape, a method using a polymer material, or the like, are been developed in the field of light weight technology. Such technology can possibly be used in a stabilizer bar applied to a chassis module, and a sub-frame, arms, or the like, applied to a drive shaft or a chassis suspension of a rally car to significantly increase fuel efficiency.
In the case of existing chassis steel, elements such as chromium (Cr), molybdenum (Mo), vanadium (V), and the like can be added to provide high strength properties. Unfortunately, a relatively simple carbide can form in a structure. The amount of the formed carbide may not be large, and its size may not be fine, thus the durability of the components may not be desirable.
In the case of high strength steel disclosed in Patent Document No. KR 10-2016-0096611, amounts of chromium (Cr) and molybdenum (Mo) used to form carbide and boride were not sufficient, and similarly, the amount of niobium (Nb) contributing to formation of the carbide was also not sufficient, such that it was difficult to improve durability while satisfying high strength.
The contents described as the related art have been provided only for assisting in the understanding for the background of the present invention and should not be considered as corresponding to the related art known to those skilled in the art.